O Level Biology Practical 2020 Answers Jun 2026

The examination was divided into investigative tasks that required both manual dexterity and theoretical application.

Always double-check that your measurements have correct units attached ( cm3cm cubed

Sample B usually showed the shortest time (highest concentration). Sample D remained blue, indicating of glucose. Positive results were indicated by a . Enzyme Activity (Catalase):

Use at least half the provided grid and a ruled best-fit line . o level biology practical 2020 answers

The exact questions vary by regional variant. This article provides the accepted answers for the most common 2020 practical scenarios.

Always include units in headers (e.g., Time / s ) and keep decimal places consistent.

Answer without "cm³/s" = zero marks.

Use a to maintain a constant temperature. Inconsistent shaking/mixing of reagents Leads to uneven reaction rates in the test tube.

| Exam Series | Paper Code | Paper Type | Availability | |-------------|------------|------------|--------------| | May/June 2020 | 5090/61 | Alternative to Practical | Question paper + mark scheme available | | October/November 2020 | 5090/31 | Practical Test | Question paper available | | October/November 2020 | 5090/61 | Alternative to Practical | Question paper available |

flowers have pendulous stamens to easily release pollen into the wind. Resources for Full Papers The examination was divided into investigative tasks that

| Incorrect Answer | Correct Answer | |------------------|----------------| | "The acid stops the browning by killing the banana cells." | The acid denatures the enzymes responsible for the browning reaction. | | "The untreated slice is darker because it is older." | The untreated slice turns brown due to enzymatic browning when oxygen reacts with phenolic compounds released from damaged cells. | | "The control is unnecessary." | The control provides a baseline to compare against; without it, you cannot determine if changes are due to the treatment or natural processes. | | "Benedict's solution is used to test for proteins." | Benedict's solution tests for reducing sugars (e.g., glucose); Biuret reagent tests for proteins. |

Examiners frequently ask students to identify limitations in the experimental design and suggest realistic improvements. Identified Error / Limitation Practical Impact Proposed Improvement